General Information

Event name: GB-91-003
Nature of the harmful event:
Seafood toxins
Event directly affected:
Toxicity detected: Yes (Approximate range: 7,488 MU.)
Associated syndrome: PSP
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes
Event occurred before in this location: No
Individuals to contact: HOWARD, Godfrey , MACDONALD, Elspeth

Location & Date

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Location: Latitude: , Longitude:
General location information: , Orkney Islands. Scotland.
HAB Area code(s): GB-20
Additional location information:
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: July 1991 - January 1992.


Causative organism known: Yes
Causative Species/Genus: Alexandrium sp. ( cells/L)
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information:
Event-related bibliography:

Environmental Conditions

Weather: Turbidity (NTU): Wind direction:
Stratified water: No Oxygen content (nL/L): Wind velocity:
Temperature (°C): Oxygen saturation %: Current Direction:
Sechhi disk (m): Salinity: Current Velocity: 0
Nutrient information:
Temperature Range During Event: Max: °C, Min: °C
Salinity Range During Event:
Bloom location in the water column:
Growth Comments Not known.
Additional Environmental information:

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Bivalve Molluscs Saxitoxins Bioassay-Mouse
Crustaceans Saxitoxins Bioassay-Mouse
Mytilus edulis Saxitoxins STX eq 91 ug/100g Bioassay-Mouse
Kit used: Type of kit used:
Additional information: PSP toxins detected in bivalve molluscs and crustaceans. Maximum toxin level found in molluscs was 7,488 MU in queen scallops from Stronsay in mid August. Highest level found in crustacea was 2,513 MU recorded in velvet crabs from Rousay in early September.
Economic losses:
Management decision: Shellfisheries all around the Orkney Islands were subject to various closure notices during the outbreak.
Additional harmful effect information:
Updated at 09:52 on 9 Oct 2020